if you use epel instead of EPEL, you use the same name as epel-release. I think that's less likely to cause duplicate epel definitions. I'd also consider adding name and mirrorlist to better match the defaults from epel-release.

```
name => "Extra Packages for Enterprise Linux $osreleasemajor - \$basearch"
mirrorlist => "https://mirrors.fedoraproject.org/metalink?repo=epel-$osreleasemajor&arch=\$basearch"
```